0引言云计算[1]是近几年最热门的互联网技术,同时也是发展最为迅速的互联网服务模式。随着云计算重心的迁移以及大数据的兴起,存储即服务(Storage-as-a-Service,SaaS)作为云计算的支撑技术迅速发展,同时单独的云存储服务(cloud storage)在商业上也得到广泛的应用,比如DropB ox、Google Drive等。云存储服务的推广,业界很快发现围绕个人数据的可用性和安全性是云存储服务推广的最大障碍。用户对于云存储服务提供 0 Introduction Cloud computing [1] is the hottest Internet technology in recent years and is also the most rapidly developing Internet service model. With the shift in the focus of cloud computing and the rise of big data, Storage-as-a-Service (SaaS) is rapidly growing as a support technology for cloud computing, and a separate cloud storage service is commercially Get a wide range of applications, such as DropBox, Google Drive and so on. As cloud storage services are rolled out, the industry quickly finds the biggest impediment to the rollout of cloud storage services around the availability and security of personal data. User is provided for cloud storage service